Well, 2,3,4, and 5 are elements of modern writing that were used in detective novels in the early part of the 20th century, around the twenties. It's an American style of writing that is direct and to the point. Yes, I know Orwell was British but he wrote "Politics and the English Language" in 1946, over twenty years after the move away from baroque writing styles happened in the U.S. Hemingway, Steinbeck, Raymond Chandler all wrote in this style.
This works great in a story because you drag the reader by the neck into the plot but I think a writer of web content can risk becoming overly dry. The advice is good, but there are other elements that elevate web copy as you would find it on Wikipedia to web copy as you would find it on NatGeo, Huffington Post, Fox News Online, and the Wall Street Journal. The point is, Orwell's advice, as good as it is, will only get you half way to writing engaging content. Content that keeps website visitors reading and hitting the tell-a-friend button requires more than those good but incomplete rules for writing, imo.
So what makes the writing engaging? I would say it's what Orwell left out. That ranges from stylistic flourishes to the insertion of the personal. Style consists of, among many things, the words you use to overlay a subtle analogy over what you are discussing. You can say a fourth of July event will feature fireworks and a concert or you can tell people that the program lights the fuse on an evening of sparkling music etc. The personal elevates a piece of writing in that it gives it personality. Some people have a gift for telling a tale, the pause, selection of details, analogies and brief asides that elevate a simple description, review, how-to into really good reading that draws you in regardless if you're interested in the topic or not. Then there are writers like Malcolm Gladwell, who in my opinion are creating the written equivalent of a magic trick with a deck of cards. He takes all the pieces and arranges them in a way that leads you to certain assumptions then he flips the card in your hand and you see it's not the card you thought you were holding. That's an elaborate construction and part of the fun of reading his essays, of knowing he is setting you up and even though you know you're being set up you're still astonished when he flips the card and what you thought was true turns out to maybe not have been so true all along. It's style, what makes people like your site.
This is what I mean when I say that Orwell's rules will only take you half way. For example, Wikipedia is like a utensil for peeling potatoes. You take it out, peel the potatoes, then toss it in the sink. A website with engaging writing, writing with style, is like one of those OXO tools that you pull out and feel good when you grip it and recommend to your friends.